Essential Windows Presentation Foundation is precisely what the title says it is. What more can you ask for in a book? There are already several books on the RTM of WPF, and there are bound to be more. The unique value this one has is that it is written by Chris Anderson, who as most know, was an instrumental architect in designing WPF, and this (along with his direct connection to the others who worked on it) gives him insight that you just otherwise can't get.

In particular, I like that he often provides the thinking that went into particular design decisions. He readily admits in several places that the design of this or that was hotly debated, and one can only imagine that they would be. Having worked at a few commercial software vendors myself, I know how difficult it can be to know the best way to design a thing, and it can only be more challenging as your audience widens.

After this, the main thing that makes the book valuable is that it is deeply conceptual. The point of the book is not to be a reference, a recipie book, or a smattering of tutorials. Rather, the book provides, in a coherent form, the key principles underlying the different aspects of WPF. And by elaborating these principles, Chris establishes a strong sense that the Foundation was designed in a similarly coherent manner.

My favorite chapters were the one on Data, the one on Actions, and the Appendix. For a solutions architect and developer, these I think provide the most interesting meat. Of course, these types will likely want to delve into the first three chapters as well. In fact, the only one that I'd suggest you can probably get away with skipping is the one on Visuals; I found this one pretty dry and hard to push through. Designers and those more interested in graphics per se will likely enjoy these.

The chapter on Styles took me by surprise, but then, that's because the concept of styles in WPF is a tad surprising. Being the language-oriented person that I am, I am a bit bothered by the choice of Style to encompass everything that you can do with styles in WPF. Needless to say, it's not just UI goodness--devs will need to be pretty familiar with this stuff.

Other than that, my only contention is with the assertion that apps today are all about data. This won't come as a surprise to those who've read my articles or talked to me about architecture much, but despite my philosophical objection, when it comes to UI, I'll admit that LOB apps are in fact largely about the data, i.e., largely about displaying and manipulating data since thus far, we seem to have mainly used computers to help with data storage and retrieval. In any case, it is certainly important to have good data binding mechanisms in the UI, and I have to say, WPF nails this better than any UI tech I've bumped into thus far.

But I digress. The book is good; I recommend it as a starting point or to complement other WPF learning resources. It is the essentials with which you can start effectively creating WPF applications. You'll need the docs and/or other more comprehensive books to really figure it all out, but you should read this one regardless.